Abstract/Proposal Summary: This proposal requests funding to create public use datasets for two unique cohort studies conducted by the NICHD-funded Pediatric HIV/AIDS Cohort Study (PHACS) network. The PHACS network has conducted two US-based observational cohort studies: (1) the Surveillance Monitoring of ART Toxicities (SMARTT) study, which has enrolled almost 4000 infants and children born to HIV-infected mothers to evaluate the safety of perinatal exposure to antiretroviral (ARV) agents, and (2) the Adolescent Master Protocol (AMP) study, which evaluates the effects of HIV and ARV treatments in children and adolescents who are perinatally HIV-infected (n=451) or perinatally HIV-exposed (n=227). The SMARTT and AMP studies have collected data from face-to- face study visits, medical charts, questionnaires, laboratory assessments, and neurodevelopmental assessments, and now represent an exceptional data resource for addressing scientific questions related to HIV infection or exposure, both among adolescents who have lived with HIV infection since birth, and among a growing population of HIV-exposed and ARV-exposed children born to mothers with HIV infection. Both studies are ongoing with annual follow-up visits. The specific aims of this proposal are to create public use datasets and corresponding documentation for the SMARTT and AMP studies based on data from study entry through 2 years of follow-up. Public use datasets will be submitted to the NICHD-supported Data and Specimen Hub (DASH). Measures will be taken to protect confidentiality and privacy of patient data. The public use datasets for SMARTT and AMP will span a wide spectrum of health outcomes in these unique populations and enhance access to the wider scientific community, providing increased speed of scientific and medical research. Findings from secondary analyses will enhance care of children in HIV-affected families.